Pressure indicator and recorder.



No. 822,244. PATENTED JUNE 5, 1906 W. H. BRISTOL. PRESSURE INDICATOR ANDRECORDER.

APPLICATION FILED MAR-18, 1905.

UNITED r m a t": 'ri Uri a l lac idle PREQiSURE lNDlGrhTQPt AND FlEQQEllZW-EFL Specification of Letters Patent.

Patented dune 5, 1.906.

Application filed March. 18. 1905. Serial No. 260,745.

Ta ra/ll whom it may concern.-

Be it known that I, WILLIAM H. BRrsroL, acitiz en of the United Statesof America, residing at New Yor in the county and State of New York,have invented certain new and useful Improvements in Pressure Indicatorsand Recorders, of which the following is a specification.

My invention relates to improvements in devices for indicating orrecording pressures and variations thereof, and particularly to thatclass of pressure indicating or re ording devices in which theelongation or e.. ision of an expansible chamber is converted into adeflection, serving to indicate the existing pressure, by suitablyrestraining the movement of said chamber.

My present invention is an improvement on my former invention, patentedFebruary 4, 1890, No. 420,570, and has for its ohjcct to give greaterfreedom of motion to increase the roportionate angular motion and topermit of a diversity of scales.

For this purpose my .invention consists, essentially,

of an expansible chamber which is constrained to a definite direction ofmotion by one or more hinged restraining connections.-

My invention will best be understood when described in connec ion withthe ace omp anyin drawings, in which-- igure 1 illustrates invention toa recording device. Fig. 2 is a side view. Fig. 3 is anenlarged'cross-sectional view. Figs. 4 to 7 are views showingmodifications.

Similar numerals of reference designate corresponding parts throughoutthe several views.

Referring now to the drawings, 1 is a case of any suitable indicating orrecording mechanism provided with a dial 2, upon which a continuousrecord of the pressure is made.

3 is a connecting-pipe through which the pressure to be measured isbrought to the instrument.

4 is a perforated head secured to the pipe 3 and to the case and adaptedto form one on of the expansible chamber 5. This expansible chamber isclosed at the top and has anon-flexible plate 6, to which is attachedthe .pointer 7. It is composed of a series of SB(. tions of perforateddiaphragms either plain or corrugated or may consist simply of a sin- 55gle expansible section.

Internal pressure applied to the chamber 5 the application of my willcause it to expand. To utilize this eX- pansion for the purpose ormeasuring the pressure, I restrain the elongation or expan sionpreferably by two rigid pie es 8, each provided with at least one hingedpart, so as to be capable of free rotation in a definite plane. W hentwo pieces them on opposite sides of the chamber 5 and so connect themto said chamber that their plane is parallel to the of normal expan sionof the chamber, as shown in Figs. 1 to 3 and 5 and 7, or inclined to it,as

hown in Fig. 6. As shown in Figs. 1 to 3, this hinged connection is inthe form of a knife-edge hearing at the top and bottom of the chamber 5.course the connection may be rigid at the top and hinged only at thebottom, as shown in Fig. 4:. The piece 8 may he composed of one or twoparts, and in the latter case both may respectively, and the hingedconnection made intermediate, as shown in Fig. 5. The degree of angularmotion will depend upon the relative positions of the bearings, antherefore a considerable variation is possi e. Further, I am enabled toobtain great diversity of scales by varying the location of the upperand lower connections ior example, as shown in Fig. 6.

I do not wish to restrict myself to any par-- ticular form of hingedconnection and by this term desire to be understood as'meaning any ofthe well-lrn nvn forms oi bearings, such pin, knife-edge, piv ot, orroller.

In order to determine the positive zero position of the pointer, I placethe chamber under a slight initial tension in adjusting the pieces 8. Incase the spring effect c the chamber is not suiiicient to produce thenecessary initial tension 1 provide an ad 9, as shown in Fig. r, inwhich is connected to the rigid sides of the chamber 5 by some flexiblematerial, such as rubber, leather, 85c. Unless a'spring be provided forthis chamber there is no certainty that the pointer will assume adefinite zero position, as in the case of the expansible chambercomposed of a series of perforated diaphragms, which of themselves actas a spring, nor will it promptly return on decrease in pressure. By makng the tension of this spring adjustable, as by the winged nut 10, andmaking the plate 6 large and the bearings knife-edge bearings I obtain.an instrument responsive to the slightest variations of pressure. Alsoby varying the ten justable spring a single plate 6 are used, l place berigidly connected to the top and'bottom,

I sion of the spring 9 I am enabled to use the same instrument fordifferent ranges of pressure.

I do not wishto restrict myself tdany particular location of the hingedconnection nor to any particular form of hinged connection, and What Iclaim as new, and desire to secure by Letters Patent, is

1. In a pressure indicator or recorder; the combination with anexpansible chamber, of hinged restra ning means adapted to convert theexpansion of said chamber into a deflection of the same.

2. In a pressure indicator or recorder; the combination with anexpansible chamber, of hinged restraining means adapted to convert theexpansion of said chamber into a defiection of the same, and anindicating-arm attached to said chamber.

3. In a pressure indicator or recorder; thecombination with anexpansible chamber composed of a series of perforated diaphragms, ofhinged restrainin means adapt,- ed to convert the expansion. oi saidchamber into a deflection of the same.

4. In a pressure indicator or recorder; the combination with anexpansible chamber composed of a series of a perforated diaphragms, ofhinged restraining means adapted to convert the expansion of saidchamber to convert the expansion of said chamber.

into a deflection of the same. 7. In a pressure indicator or recorder;the combination with an expanslble chamber, of

two hinged restraining pieces adapted to convcrt the expansion of saidchamber into a de- .30 into a deflection of the same, andan indicat- Ii'lection, the common plane of said pieces being at right angles to thedirection of deflection of the same.

In testimonv whereof I have signed my name to this specification, in thepresence of two subscribing witnesses, this 16th day of March, 1905.

WILLIAM H. BRISTOL. Witnesses:

A. FABER DU FAUR, RAENA H. YUnIzK.

